输出系统日期和时间

Question

代码没问题，为什么运行不了啊

代码如下：

include<stdio.h>

include<time.h>

int main()
{

int command[4] = { 0,1,2,3 };
int num;
struct tm* sysTime;
printf("如需帮助可输入数字:0!\0");
printf("请输入命令符:\n");


while (1)
{
    scanf_s("%d", &num);
    if (command[0] == num)
    {
        printf("输入数字1显示系统日期,输入数字2显示系统时间,输入数字3退出系统!\n");
    }
    else if (command[1] == num)
    {
        time_t nowTime;
        time(&nowTime);
        sysTime = localtime(&nowTime);
        printf("系统日期:%d-%d-%d\n", 1900 + sysTime->tm_year, sysTime->tm_mon + 1, sysTime->tm_mday);
    }
    else if (command[2] == num)
    {
        time_t nowTime;
        time(&nowTime);
        sysTime = localtime(&nowTime);
        printf("系统时间:%d:%d:%d\n", sysTime->tm_hour, sysTime->tm_min, sysTime->tm_sec);
    }
    else if (command[3] == num)
    {
        return 0;
    }
    printf("请输入命令符:\n");
}
return 0;

}

谢谢